Upgrade of Java Quiz: Metamorphic Rocks

Metamorphic rocks are those that form when any pre-existing rock is permanently altered, or metamorphosed, in it's lithology (texture and/or mineral content)due to the high heat, the high pressure, and/or the presence of chemically acitve fluids (water)in deep burial environments. The heat gradient will produce different structural silicates (in reverse of Bownen's reaction series). The high pressure can be due to the weight-of-burial (lithostatic) pressure or to the directed pressure during mountain building. The presence of water acts as a catalyst for change by lowering temperatures of crystallization and as a "conduit" of ion and molecule movement.